Octopus Flux: The Best Tariff for Solar Battery Owners
Octopus Flux is the most financially rewarding electricity tariff available to UK homeowners with both solar panels and battery storage in 2026. Unlike standard time-of-use tariffs that simply offer cheap overnight rates, Flux creates a three-way arbitrage: cheap overnight import, cheap daytime generation (your own solar), and premium export rates during peak evening demand. Getting the most from Flux requires understanding how it works and how to configure your battery correctly.
How Octopus Flux Works
Flux operates across three daily periods:
- Off-peak (02:00–05:00): Import rate approximately 8–9p/kWh. Charge your battery cheaply.
- Standard daytime (05:00–16:00 and 19:00–02:00): Import rate approximately 22–26p/kWh. Your solar generation should cover daytime usage. Battery holds charge from overnight.
- Peak (16:00–19:00): Import rate approximately 35–40p/kWh — expensive. But also the peak export rate: Flux pays approximately 25–32p/kWh for electricity you export during this window. Discharge your battery during these three hours.
The arithmetic: charge 9.5kWh overnight at 8.5p = £0.81 cost. Discharge during peak at 28p export rate = £2.66 income. Net income per cycle from just the import/export arbitrage: £1.85. Add in self-consumption savings from both overnight charging and solar, and total daily financial benefit is typically £2.50–£4.00 for a well-optimised setup.
Battery Configuration for Flux
Correct battery scheduling is essential for Flux to deliver its financial potential. The recommended profile for most systems:
- 02:00–05:00: Force charge to 95–100%. Import at off-peak rate.
- 05:00–16:00: Allow solar to top up battery if it has discharged. Maintain minimum reserve of 20%.
- 16:00–19:00: Force discharge to minimum reserve (typically 10–20%). Export to grid at peak rate.
- 19:00–02:00: Standard mode — use battery for self-consumption, allow it to drop to minimum before overnight charge window.
GivEnergy Gen 3 batteries handle this scheduling natively via the GivEnergy portal. Tesla Powerwall uses Time-Based Control with custom peak periods. FOX ESS and Sigenergy both support this scheduling through their respective apps. ALPS Electrical configures all batteries for optimal Flux performance at commissioning for customers who confirm their Octopus tariff preference before installation day.
Annual Income from Octopus Flux
For a typical North East home with a 4kW solar system and 9.5kWh battery:
- Self-consumption saving (solar, no battery): ~£600–£800/year
- Additional self-consumption (battery): ~£350–£500/year
- Peak export income (Flux): ~£350–£550/year
- Import saving (overnight cheap charging): ~£200–£350/year
- Total estimated annual benefit (Flux, full setup): ~£1,500–£2,200/year
These figures assume approximately 250 Flux-optimised cycles per year (accounting for weekends and seasonal variation in solar). Actual results depend on battery usage patterns, household consumption and the specific Flux rates at time of calculation.
Is Flux Better Than Octopus Go?
For battery owners with solar: generally yes, Flux delivers higher total returns. For battery-only households (no solar): Octopus Intelligent Go often outperforms Flux because the smart charging slots frequently achieve rates below 2p/kWh, whereas Flux's off-peak rate is fixed at ~8–9p/kWh. The break-even depends on your solar generation volume and battery size — a free energy audit comparing both tariff profiles for your specific setup is the most accurate way to determine the better option.
Get a Flux-Ready Battery Installation
For North East homeowners, ALPS Electrical provides Flux-configured solar and battery installations across Teesside, County Durham and North Yorkshire. We install GivEnergy, Tesla Powerwall, FOX ESS and Sigenergy — all configured for Flux optimisation at commissioning. See our battery storage service for more information.
Switching to Flux: Practical Checklist
If you already have solar and battery storage and are considering switching to Octopus Flux, here is a practical checklist before you make the move:
- Check your battery's scheduling capability: Flux requires the ability to force-charge during 02:00–05:00 and force-discharge during 16:00–19:00. Most modern batteries support this — GivEnergy, Tesla Powerwall 3 (via Time-Based Control), FOX ESS and Sigenergy all do. Older first-generation batteries may lack the flexibility.
- Check your current tariff exit terms: Some fixed-rate tariffs charge exit fees if you leave before the contract end date. Flexible tariffs (Octopus Tracker, Agile) can be switched immediately.
- Confirm Octopus availability: Octopus Flux is only available to Octopus Energy customers. If you are with a different supplier, you will need to switch your energy supplier as well as your tariff.
- Review your consumption profile: Flux works best for households with significant evening consumption (5–10pm) and morning consumption (6–9am) when grid draw would otherwise be at standard or peak rates. Households with very low evening consumption will see reduced benefit from Flux's peak export premium since they have less grid draw to offset.
Flux in Winter: Does It Still Work?
Winter reduces solar generation significantly — a North East home generating 350–400 kWh/month in summer may generate only 80–120 kWh in December. This reduces the self-consumption component of Flux savings. However, the import/export arbitrage (charge cheap at 02:00–05:00, export at peak 16:00–19:00) remains year-round and is independent of solar generation. For households using Flux with battery-only (no solar or minimal winter solar), the annual return is lower but still typically £400–£700 per year from the arbitrage cycle alone. Winter is also when peak export rates on Flux tend to be at their highest, partially compensating for reduced solar.
The Future of Variable Tariffs
Flux, Agile, and Intelligent Go represent the leading edge of a broader shift toward dynamic electricity pricing in the UK. Ofgem's review of retail electricity tariffs is expected to accelerate the move to half-hourly settlement for all customers by 2027, which will make time-of-use tariffs the default rather than the exception. Homeowners who invest in battery storage and smart EV chargers now are best placed to extract maximum value from this pricing shift as it matures.